Flexible Organic Solar Cells: Nanoscale Phase Separation and High Photovoltaic Efficiency in Solution-Processed, Small-Molecule Bulk Heterojunction Solar Cells (Adv. Funct. Mater. 19/2009)

The inside cover of this issue illustrates the fabrication of lightweight and flexible organic solar cells, developed by B. Walker et al. on page 3063, from a solution of fullerene and diketopyrrolopyrrole-based materials. The texture of the organic film on the substrate was taken from an atomic force microscope phase image of the high performance device (4.4% power conversion efficiency), showing the phase separation behavior of the two molecular semiconducting materials.